Hoist.



V PATENTED AUG. 14, 1906. A. J. BURBANK.

APPLICATION FILED NOV. 13, 1905.

,- WITNESSES NVENTOR A TTORN E 7.5

UNITED STATES A'IENI OFFIGE.

ABNER J. BURBANK, OF HARVARD, ILLINOIS, ASSIGNOR TO THE MIL- WAUKEE HAY TOOL COMPANY, OF MILIVAUKEE, ISCONSIN.

HOIST.

Specification of Letters Patent.

Patented Aug. 14, 1906.

Application filed November 18, 1905. Serial No. 286.999.

T at whom 711? 777/6711] concern:

Be it known that I, ABNER J. BURBANK, a citizen of the United States, residing at the town of Harvard, county of HcHenry, and State of Illinois, have invented new and useful Improvements in Hoists, of which the following is a specification.

My invention relates to improvements in hoists, and such improvements pertain more especially to the peculiar construction, location, and arrangement of the mechanism for clamping and unclamping the hoisting-rope by the lateral movement of its free end, whereby the load which is being raised by the hoist maybe suspended at any desired point.

The construction of my invention is explained by reference to the accompanying drawings, in which Figure 1 represents a side view, part broken away to show the interior; and Fig. 2

represents a front view thereof.

Like parts are identified by the same reference characters in both views.

My hoist comprises, among other things, a sheave-block 1, pulleys 2 and 3, hoistingrope 4, two-arm lever 5, which lever is pivotally supported at a point between its respective ends from the sheave-block 1 upon the pulley-supporting axle 6, and a clamping cam 7, which clamping-cam is pivotally supported from the sheave-block upon a transverse pin 8. The two-arm lever 5 is provided at one end with a guiding-channel 9 for the free end 10 of the rope 4, while the opposite end of said two-arm lever is pro vided With cam-actuating bearings 11, which loosely engage the lateral projections 12, formed on the side of the clamping-cam 7.

Owing to the fact that the lateral movement of the free end of the rope in the act of operating the clamping-cam is applied to the long arm of the lever 5 and from thence through the short arm 14 thereof to the clamping-cam, the power applied to the free end of the rope is multiplied, so that the clamping-cam 7 is caused to impinge more firmly against the surface of the rope than it would otherwise do were the arms of said lever of equal length, whereby but little effort on the part of the operator is required for operating the clamping-cam and throwing it into and out of engagement with the hoisting-rope. The bearing-surface of the clamping-cam 7 is preferably serrated, as shown,

whereby it is caused to more effectively hold a hoisting-rope.

Having thus described my invention,what I claim as new, and desire to secure by Letters Patent, is'- 1. The combination with a sheave-block, pulley and hoisting-rope, of a clamping-cam pivotally connected with the sheave-block, and a two-arm lever pivotally supported from the pulley-axle, one end of said twoarm lever being provided with a sleeve for the reception of the free end of the hoistingrope and the opposite end being provided with slots adapted to engage laterally-projecting pivots formed on the respective sides of the clamping-cam, substantially as set forth.

2. The combination with a sheave-block, pulley and hoisting-rope of a clamping-cam pivotally suspended between the vertical walls of the sheave-block above the pulley, a two-arm lever pivotally suspended from the pulley-axle between the walls of the sheaveblock, the lower arm of said lever being provided with a channel for the free end of the hoisting-rope and the opposite arm of said lever being provided with pivotal bearings adapted to engage and operate the clamping- Canl.

In testimony whereof I afiix my signature in the presence of two witnesses.

ABNER J. BURBANK. Witnesses:

II. D. CRUMB, R. G. EHLE. 

